Fix corner-case in heap size estimation.

Fix corner-case in heap size estimation.

Empty but unswept pages could cause the unswept_free_bytes counter to
to be off in case heap gets shrunk and page gets released before it was
swept properly.

R=vegorov@chromium.org
BUG=v8:1893
Committed: https://code.google.com/p/v8/source/detail?r=10421

[Vyacheslav Egorov (Chromium), 2012-01-17 13:49:37]

lgtm

with a better name for Mark/Unmark routines :-)

http://codereview.chromium.org/9241010/diff/1/src/mark-compact.cc
File src/mark-compact.cc (right):

http://codereview.chromium.org/9241010/diff/1/src/mark-compact.cc#newcode3636
src/mark-compact.cc:3636: space->MarkPageForLazySweeping(p);
this is pretty confusing. we are both marking it for lazy sweepign and releasing
it immediately.

maybe rename MarkPageForLazySweeping into something else?

[Michael Starzinger, 2012-01-17 14:09:38]

Added new patch set. Landed.

http://codereview.chromium.org/9241010/diff/1/src/mark-compact.cc
File src/mark-compact.cc (right):

http://codereview.chromium.org/9241010/diff/1/src/mark-compact.cc#newcode3636
src/mark-compact.cc:3636: space->MarkPageForLazySweeping(p);
On 2012/01/17 13:49:37, Vyacheslav Egorov wrote:
> this is pretty confusing. we are both marking it for lazy sweepign and
releasing
> it immediately.
> 
> maybe rename MarkPageForLazySweeping into something else?

Done. As discussed offline we chose IncreaseUnsweptFreeBytes  (and the Decrease
counterpart) to be a suitable name here.